Exercise 1. Mark the letter A, B, C, or D to indicate the correct to each of the following questions. 1. A correction pen is used for ____ your writing mistakes. A. cover B. covered C. covering D. to cover 2. It's no good ____ him the truth now. A. not to tell B. tell C. telling D. to tell 3. It's important ____ too much about your failure. A. not to worry B. not worry C. not worrying to D. don’t worry 4. Don’t forget ____ your homework before coming to class. A. doing B. having done C. to be done D. to do 5. Did you remember ____ Mr. Green my message? A. be given B. giving C. have given D. to give